A heating, ventilation, air conditioning and refrigeration system includes a heat transfer fluid circulation loop configured to circulate a refrigerant therethrough, a purge gas outlet in operable communication with the heat transfer fluid circulation loop and at least one gas permeable membrane having a first side in operable communication with the purge gas outlet and a second side. The membrane includes a plurality of pores of a size to allow passage of contaminants through the membrane, while restricting passage of the refrigerant through the membrane, and further restricting passage of a vapor phase corrosion inhibitor through the membrane. A purge unit is in operable communication with the second side of the permeable membrane configured to receive a purge gas from the permeable membrane.